User’s Manual
C166S V1 SubSystem
Central Processing Unit
User’s Manual
3-25
V 1.6, 2001-08
The C166S makes it possible to switch the complete register bank of CPU registers
(GPRs) with a single instruction, so the service routine executes within its own separate
context. The instruction “SCXT CP, #New_Bank” pushes the contents of the Context
Pointer (CP) into the system stack and loads the CP with the immediate value
“New_Bank”. The new CP value sets a new register bank. The service routine may now
use its own registers. This register bank is preserved when the service routine is
terminated, i.e., its contents are available for the next call. Before returning (RETI), the
previous CP is simply popped from the system stack, which returns the registers to the
original register bank.
Note: Resources that are used by the interrupting program must eventually be saved
Pointers (DPP) and the registers of the multiply and divide unit.
Note: The first instruction following the SCXT CP,... instruction must not use a GPR.
Содержание C166S V1 SubSystem
Страница 10: ...User s Manual C166S V1 SubSystem User s Manual I 6 V 1 6 2001 08...
Страница 16: ...User s Manual C166S V1 SubSystem Introduction User s Manual 1 6 V 1 6 2001 08...
Страница 126: ...User s Manual C166S V1 SubSystem Central Processing Unit User s Manual 3 96 V 1 6 2001 08...
Страница 178: ...User s Manual C166S V1 SubSystem Memory Organization User s Manual 4 52 V 1 6 2001 08...
Страница 206: ...User s Manual C166S V1 SubSystem Instruction Set User s Manual 5 28 V 1 6 2001 08...
Страница 306: ...User s Manual C166S V1 SubSystem Detailed Instruction Set User s Manual 6 100 V 1 6 2001 08...
Страница 362: ...User s Manual C166S V1 SubSystem The External Bus Interface User s Manual 8 40 V 1 6 2001 08...
Страница 452: ...User s Manual C166S V1 SubSystem General Purpose Timer Unit User s Manual 12 44 V 1 6 2001 08...
Страница 454: ...User s Manual C166S V1 SubSystem Instruction Index User s Manual 13 2 V 1 6 2001 08...
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